This topics been done to death here
http://forums.overclockers.co.uk/showthread.php?t=18698497
and other places...
no the doubt
thesuperlouis and
Simon Belmont with be along shortly to tell you to buy Skylake as its newer with (slightly) better per core clocking (i.e. maximum per core overclock potential) and better IPC (instructions per clock) that Haswell/ Haswell-E.
This is what I would suggest you consider:
6700K
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Pros
- cool/low power
- access to modern motherboard features i.e. full speed m.2 slots and USB 3.1
- fairly good clocker (maximum attainable GHz overclocked)
- Current best IPC per clock (amount of instuctions that can be dealt with within a clock cycle)
Cons
- stupidly expensive due to shortages and suspected price gouging by Intel to recoup money lost getting their CPU's down to 14nm. The core itself is comparable to the size of a previous gen i3 and traditionally the size of a core has been a key factor in the cost of a CPU. As a smaller core means more CPU's can be made from a production wafer.
- Doesn't clock (maximum attainable GHz) better that previous generations of consumer CPU's
- Your paying for an iGPU that your unlikely to use much if your a gamer/enthusiast
- You will be limited in the future to a 4 core / 8 threaded CPU - this may become crucial if high end gaming shifts to take advantage of more cores in the future.
Given the trouble Intel has maintaining progress with CPU die shrinks at the moment I suspect there will be a renewed focus on selling CPU's with more cores as a selling point for future platforms and gaming's likely to go more multi threaded in the future with API's like DX12 coming into use. If your looking to keep your motherboard for a few years you may find Skylake/Z170 very limiting in the future
- Less PCI-E lanes (potentially by a lot depending on CPU used) compared to X99.
With my old X58 setup with SLI'd GPU's I was still able to add a super fast PCI-SSD and an add in card which gave me USB3 and SATA3 due to the extra PCI-E lanes you get with the enthusiast CPU's by default of the consumer CPU's and motherboards
6600K
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Pro's
Much cheaper than 6700K - still overclocks well. IPC improvements of Skylake over previous generations of CPU as per 6700K
Cons
- No HT (hyperthreading) so stuck with four cores and threads which may hold you back going forward with games and will severely hold you back in situations were programs are heavily multithreaded
- still expensive compared to previous i5's but arguably not as bad as the 6700k
5820K
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Pro's
- 50% more cores and threads than 6700k - will massively outperform it when using heavily threaded programs
- Costs less for the CPU with similar total cost when comparable motherboard and memory added
- More PCI-E lanes allowing more expansion in the future
- access to same modern motherboard features as Z170. There's nothing you can get with Z170 that you cant get with X99 from the motherboards available.
- Quad channel memory with more maximum bandwidth (unlikely to be relevant yet as Skylake has a sufficiently large amount of bandwidth as it is)
- access to 14nm CPU's in the future (Broadwell-E) that will have 6 cores/ 12 threads + likely to have more longevity as a platform due to this and extra PCI-E lanes
- Overclocks generally to within 200mhz of a 6700k. Games are not currently CPU limited - they are GPU limited. To show the benefit of a 6700K you have to run a silly setup (i.e 1080p with a Titan-X) to show any meaningful benefit. By the time the CPU becomes more limiting with faster future GPU's games will likely take advantage of more than four cores so 5820k may be even faster than 6700k despite lower clocks per core.
- No money/ die space wasted on iGPU
Cons
More cores, threads and larger process for manufacture means more heat generated and power used. CPU refresh Broadwell-E should show good gains with drop to 14nm. The refresh for Skylake with be Kabylake still at 14nm early indications are that the iGPU will be getting most of the attention with this refresh so likely less CPU gain over Skylake then Haswell-E to Broadwell-E
less IPC and maximum overclock - much lower stock speed
Conclusions
Basically the 6700k is not a bad CPU per say its price just makes it hard to justify.
If u need a threaded or HT CPU U need X99. 6700K really has no place currently.
Where you don't need more than four threads the 6600k is a good option than gives access to modern motherboard features as per 6700K but for more than 100 notes less
The 5820K currently offers great value for money is a great all rounder and the X99 motherboards have a greater potential longevity compared to Z170 boards
